We got my mum's old (55) citroen C4 about 6 months ago. It's a lovely car to drive but mum forgot to mention that the back passenger doors freeze shut when it's very cold. It wasn't a problem for her; there were only two of them and they lived on the south coast. I'm on the East midlands with a 3 year old (who was banned from sitting in the front passenger seat when he grabbed the gearstick and put the car into neutral at 70 mph), so I need to find a solution to this to get the rear doors working.
If you've had a car where some of the doors freeze shut, how did you resolve this? We're parked on the road, and don't have a garage, and have tried spraying everything metal to do with the rear doors' mechanisms with WD40, but it hasn't worked. I'm just getting tired of having a 3 year old trample over the front passenger seat to get in the car, and having to grope around from the front seats to fasten him in.